Rule 120.3 · Damage
Damage may have one or more of the following results, depending on whether the recipient of the damage is a player or permanent, the characteristics of the damage’s source, and the characteristics of the damage’s recipient (if it’s a permanent).
Subrules
Damage dealt to a player by a source without infect causes that player to lose that much life.
Damage dealt to a player by a source with infect causes that source’s controller to give the player that many poison counters.
Damage dealt to a planeswalker causes that many loyalty counters to be removed from that planeswalker.
Damage dealt to a creature by a source with wither and/or infect causes that source’s controller to put that many -1/-1 counters on that creature.
Damage dealt to a creature by a source with neither wither nor infect causes that much damage to be marked on that creature.
Damage dealt by a source with lifelink causes that source’s controller to gain that much life, in addition to the damage’s other results.
Combat damage dealt to a player by a creature with toxic causes that creature’s controller to give the player a number of poison counters equal to that creature’s total toxic value, in addition to the damage’s other results. See rule 702.164, “Toxic.”
Damage dealt to a battle causes that many defense counters to be removed from that battle.